International Standard Book Number, the international code for identifying a particular version or printing of a book
<!ELEMENT isbn (#PCDATA) >
Text, numbers, or special characters
<citation> Citation; <product> Product Information; <related-article> Related Article Information
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<article-meta>
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<volume>318</volume>
<issue>7187</issue>
<fpage>837</fpage>
<lpage>841</lpage>
<product>
<name><surname>Lapeyre</surname>
<given-names>Deborah A.</given-names>
</name>
<name><surname>Usdin</surname>
<given-names>B. Tommie</given-names>
</name>
<source>Wildflowers of the Washington Area</source>
<year>2002</year>
<publisher-name>Lippman, Ltd.</publisher-name>
<publisher-loc>Bethesda, MD</publisher-loc>
<isbn>0-23-8675-309</isbn>, includes a CD-ROM,
<price>$19.95</price> (Used 12.50 when available)
</product>
<history>
<date date-type="accepted">
<day>29</day><month>01</month>
<year>1999</year></date></history>
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</article-meta>
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